After-chromable acid dyestuffs of the triphenylmethane series



Patented Apr. 2, .1940

' UNITED STATES AFTER-CHBOMABLE i "PA ENT ounce THE 'TRIPHENYLMETHANE SERIES Paul Wolff and Hal 1s Moehrke, Frankfort-onthe-Main-Hochst, Germany, assignors to Gen-v eral Aniline & Film Corporation, a corporation of Delaware v No Drawing. Application May 13, 1938, Serial No. 207,790. In Germany June 3, 1937 4 Claims. (Cl. 260-390) The present invention relates to afterchromable acid dyestuffs of the triphenylmethane series.

We have found that valuable dyestuffs capable of being chromed may be obtained by causing an aromatic monoalkylamine to react with a tri-' phenylmethane-dyestuif carrying. at least one group capable of being chromed, i. e. a hydroxy and a carboxy group in ortho-position to each other, and in para-position to the methane carbon atom a halogen atom. The new dyestuffs have a considerably better fastness to alkalies than those obtained from the known chromable dyestuffs of the triphenylmethane series containing in paraposition to themethane carbon atom a halogen atom by reaction with a primary aromatic amine.

The following examples serve to illustrate the invention, but they are not intended to limit it thereto:

1. The dyestuff obtainable by condensing 1 mol of l-chlorobenzaldehyde with 2 mols of 1 hydroxy 5 methylbenzene 2 carboxylic acid (meta-cresotic acid) and subsequent oxidation (of. example of U. S.-Patent No. 1,065,405) is melted for several hours atabout C. to

C. in the form of its free acid with an excess of ethylaminobenzene in the presence of water until the originally thinly liquid melt has changed to a powder finely suspended in water. The ethyl- I aminobenzene in. excess is removed by stirring with dilute hydrochloric acid and. a dyestuff is thus obtained which dyes wool, when afterj chromed, vivid blue tints. The dyestufi has probably the following constitution:

CH3 CH3 HO O i C O OH CzHn-N-CoHs 2. By substituting in the process of Example 1 g the equivalent amount of l-methylaminoimethylbenzene for the ethylaminobenzene used and otherwise proceeding as indicated in that example, a dyestuff is obtained which dies wool,

when after-chromed, clear blue tints of a some- 1. The compounds of the general formula:

- out CH:

| on. I

H000 I coon x-N Y' wherein X represents an alkyl of the group consisting of methyl and ethyl and Y represents an aryl'group of the phenyl series, said compounds being chromable dyestuffs dyeing wool vivid gbluish tints. v

2. The compound of the formula:

' CH: CH; OH

HOOC COOH ,otHtNctHt being a dye'stufi which dyes wool, when afterchromed, vivid blue tints. I

3. The compound of the formula: I

CH3 com I OH I HO-c onm-Q-Cm dyeing wool, when after-chromed, clear bluish tints. I 1

4. The compound of the formula:

011. cm t H I coon CHFN--OCH8 being a dyestufi which dyes wool, when afterchromed, vivid bluish tints.

PAUL WOLFF.

HANS MOEI-IRKE. 

